NBT Reduction Research Articles

Antioxidant Effects of Tryptanthrin Oxime.

We studied the radical-binding and antioxidant activities of the alkaloid tryptanthrin (TR) and its new synthetic derivative tryptanthrin oxime (TR-Ox), as well as the cytoprotective activity of TR-Ox under conditions of oxidative stress. The antiradical activity of TR-Ox was revealed in the test of binding with stable chromogen radical 2,2-diphenyl-1-picrylhydrazyl and in the superoxide radical generation test (riboflavin photoreduction reaction with detection by NBT reduction). TR-Ox was inferior to ionol and dihydroquercetin by the antiradical activity. In these tests, TR did not exhibit antiradical activity. TR-Ox did not show iron-chelating activity (in the test with the formation of the o-phenanthroline-Fe2+ complex and its destruction in the presence of chelating agents). In brain homogenate, TR-Ox significantly reduced the increase in spontaneous chemiluminescence. Under conditions of oxidative stress induced by 15 mM H2O2 in the SH-SY5Y neuroblastoma cell culture, TR-Ox exhibited cytoprotective activity and increased the number of viable cells.

Abstract 264: Differentiation therapy: Esculetin as a potent agent to alter cellular plasticity of leukemic & solid tumor stem cells

Abstract Background The “Differentiation therapy” has been emerging as a promising and more effective strategy against acute leukemia relapses. Objective In extension to the revolutionising therapeutic outcomes of All Trans Retinoic Acid (ATRA) to induce terminal differentiation of Acute Promyelocytic Leukemic (APL) blast cells, we decipher the potential effect of a natural compound “Esculetin” to serve as a differentiating agent in Acute Myeloid Leukemia (AML) as well as solid tumour cells. Underlaying role of Wnt signaling pathways in esculetin mediated blast cell differentiation was also evaluated. Methods Human acute myeloid leukemic cells (Kasumi-1) with t(8;21/AML-ETO) translocation were used as a model system. Growth inhibitory and cytotoxic activity of esculetin were analysed using growth kinetics and MTT assay. Morphological alterations, cell scatter characteristics, NBT reduction assay and cell surface marker expression pat- terns were analysed to detect terminally differentiated phenotypes. We employed RT2profiler PCR array system for the analysis of transcriptome profile of Wnt signaling components. Calcium inhibitors (TMB8 and Amlodipine) and Transforming growth factor beta (TGF-β) were used to modulate the Wnt signaling axes. To investigate whether esculetin exerts the similar effects on the invasive solid tumour cancer stem cells subset, we used a cellular model system of colon carcinoma HCT116 cells reflecting EMT phenotype. Results We illustrate cytotoxic as well as blast cell differentiation potential of esculetin on Kasumi-1 cells. Morphological alterations akin to neutrophilic differentiation as well as the corresponding acquisition of myeloid lineage markers indicate terminal differentiation potential of esculetin in leukemic blast cells. Exposure to esculetin also resulted in downregulation of canonical Wnt axis while upto ~ 21 fold upregulation of non-canonical axis associated genes. Esculetin also showed potential to revert the CSC marker expressions and concurrent EMT consistent with reduced functional aggressiveness in colon cancer cells. Conclusions Our study highlights the importance of selective use of calcium pools as well as “axis shift” of the canonical to non-canonical Wnt signaling upon esculetin treatment which might abrogate the inherent proliferation to release maturation arrest and induce the differentiation in leukemic blast cells as well as CSC stem cells. The current findings provide further therapeutic interventions to consider esculetin as a potent differentiating agent to counteract relapses. Citation Format: Ankit Mathur, Daman Saluja. Differentiation therapy: Esculetin as a potent agent to alter cellular plasticity of leukemic & solid tumor stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 264.

MiR-125b-5p-MAPK1-C/EBPα feedback loop regulates all-trans retinoic acid resistance in acute promyelocytic leukemia

BackgroundVarious studies have highlighted the significance of miR-125b-5p in tumour chemotherapy resistance; However, whether miR-125b-5p is associated with all-trans retinoic acid (ATRA) resistance in acute promyelocytic leukemia (APL) has not been reported. MethodsDrug-resistance-related factors in APL were predicted using the DRESIS database. The expression levels of miR-125b-5p in ATRA-sensitive and ATRA-resistant APL cells were determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR). A nitrotetrazolium blue (NBT) reduction assay and flow cytometry (FCM) were used to detect the effect of miR-125b-5p on ATRA resistance in APL cells. An APL xenograft tumour mouse model was established to determine the effect of miR-125b-5p on ATRA resistance. A dual-luciferase gene reporter assay, qRT-PCR, and western blotting verified the regulation by miR-125b-5p of its target gene, MAPK1, and the MAPK1 downstream factor, C/EBPα. An NBT reduction assay and FCM were used to detect the effect of C/EBPα on ATRA resistance in APL cells. Western blotting and qRT-PCR were used to assess the regulation of miR-125b-5p and MAPK1 by C/EBPα. ResultsmiR-125b-5p expression levels were dramatically increased in ATRA-resistant APL cells. Both in vitro and in vivo experiments revealed that miR-125b-5p overexpression enhanced ATRA resistance in APL. miR-125b-5p promoted ATRA resistance by sponging MAPK1. C/EBPα was negatively regulated by miR-125b-5p, which in addition, regulated ATRA resistance in APL cells. C/EBPα also regulated the miR-125b-5p-MAPK1 axis. ConclusionThe findings of this study indicate that the miR-125b-5p-MAPK1-C/EBPα feedback loop regulated ATRA resistance in APL. Thus, miR-125b-5p may be a promising target for treating ATRA resistance in APL.

Fructooligosaccharide and Bacillus subtilis synbiotic combination promoted disease resistance, but not growth performance, is additive in fish

Species diversification from major to minor carps for their sturdiness and initial higher growth, and also a quest for antibiotic-free aqua farming in the subcontinent, mandates search for and evaluation of alternatives. An experiment was performed to investigate the potential of fructooligosaccharide (FOS) and Bacillus subtilis (BS) (alone or as synbiotics) in promoting growth and immunity against infections in Labeo fimbriatus fingerlings. Six iso-nitrogenous and iso-lipidic diets containing combinations of two levels of FOS (0% and 0.5%) and three levels of BS (0, 104, 106 CFU/g feed) were fed to fish for 60 days. At the end of the feeding trial, twenty-four fish from each group were injected intra-peritoneally with pathogenic strain of Aeromonas hydrophila O:18 to test the immunoprotective efficacy of the supplements against bacterial infection. BS, but not FOS, significantly improved (P < 0.05) growth and feed utilisation attributes like percentage weight gain (PWG), specific growth rate (SGR) and feed conversion ratio (FCR). There were interactive effects of FOS and BS on PWG, SGR and FCR; however, the effects were not additive in nature. These beneficial effects of BS, alone or in combination with FOS, were corroborated by increased protease activity, microvilli density and diameter and number of goblet cells. Overall beneficial effects of FOS and BS included improved erythrocyte (RBC), hemoglobin (Hb), total protein and globulin levels. Total leucocyte (WBC) count and immunological parameters like respiratory burst activity of leucocytes (NBT reduction), lysozyme activity, albumin: globulin ratio and post-challenge survival were significantly improved by both FOS and BS, and their dietary combination yielded the highest improvement in these parameters. Synergistic effects of FOS and BS as dietary supplements indicate that a combination of 106 CFU/g BS and 0.5% FOS is optimal to improve growth, feed utilisation, immune functions, and disease resistance in L. fimbriatus fingerlings.

Esculetin releases maturation arrest and induces terminal differentiation in leukemic blast cells by altering the Wnt signaling axes

BackgroundThe “Differentiation therapy” has been emerging as a promising and more effective strategy against acute leukemia relapses.ObjectiveIn extension to the revolutionising therapeutic outcomes of All Trans Retinoic Acid (ATRA) to induce terminal differentiation of Acute Promyelocytic Leukemic (APL) blast cells, we decipher the potential effect of a natural compound “Esculetin” to serve as a differentiating agent in Acute Myeloid Leukemia (AML). Underlaying role of Wnt signaling pathways in esculetin mediated blast cell differentiation was also evaluated.MethodsHuman acute myeloid leukemic cells (Kasumi-1) with t(8;21/AML-ETO) translocation were used as a model system. Growth inhibitory and cytotoxic activity of esculetin were analysed using growth kinetics and MTT assay. Morphological alterations, cell scatter characteristics, NBT reduction assay and cell surface marker expression patterns were analysed to detect terminally differentiated phenotypes. We employed RT2profiler PCR array system for the analysis of transcriptome profile of Wnt signaling components. Calcium inhibitors (TMB8 and Amlodipine) and Transforming growth factor beta (TGF-β) were used to modulate the Wnt signaling axes.ResultsWe illustrate cytotoxic as well as blast cell differentiation potential of esculetin on Kasumi-1 cells. Morphological alterations akin to neutrophilic differentiation as well as the corresponding acquisition of myeloid lineage markers indicate terminal differentiation potential of esculetin in leukemic blast cells. Exposure to esculetin also resulted in downregulation of canonical Wnt axis while upto ~ 21 fold upregulation of non-canonical axis associated genes.ConclusionsOur study highlights the importance of selective use of calcium pools as well as “axis shift” of the canonical to non-canonical Wnt signaling upon esculetin treatment which might abrogate the inherent proliferation to release maturation arrest and induce the differentiation in leukemic blast cells. The current findings provide further therapeutic interventions to consider esculetin as a potent differentiating agent to counteract AML relapses.

Differential biological responses of adherent and non-adherent (cancer and non-cancerous) cells to variable extremely low frequency magnetic fields

Extremely low-frequency electromagnetic field (ELF-EMF) induces biological effects on different cells through various signaling pathways. To study the impact of the ELF-EMF on living cells under an optimal physiological condition, we have designed and constructed a novel system that eliminates several limitations of other ELF-EMF systems. Apoptosis and cell number were assessed by flow cytometry and the Trypan Blue dye exclusion method, respectively. In vitro cell survival was evaluated by colony formation assay. The distribution of cells in the cell cycle, intracellular ROS level, and autophagy were analyzed by flow cytometer. Suspended cells differentiation was assessed by phagocytosis of latex particles and NBT reduction assay. Our results showed that response to the exposure to ELF-EMF is specific and depends on the biological state of the cell. For DU145, HUVEC, and K562 cell lines the optimum results were obtained at the frequency of 0.01 Hz, while for MDA-MB-231, the optimum response was obtained at 1 Hz. Long-term exposure to ELF-EMF in adherent cells effectively inhibited proliferation by arresting the cell population at the cell cycle G2/M phase and increased intracellular ROS level, leading to morphological changes and cell death. The K562 cells exposed to the ELF-EMF differentiate via induction of autophagy and decreasing the cell number. Our novel ELF-EMF instrument could change morphological and cell behaviors, including proliferation, differentiation, and cell death.

Solidagenone in vivo leishmanicidal activity acting in tissue repair response, and immunomodulatory capacity in Leishmania amazonensis

Leishmaniasis is a group of chronic parasitic diseases in humans caused by species of the Leishmania genus. Current treatments have high toxicity, cost, duration, limited effectiveness, significantly complex administration, and drug-resistant strains. These factors highlight the importance of research into new therapies that use drugs without toxic effects. Solidagenone (SOL), the main labdane diterpene isolated from the plant Solidago chilensis, has anti-inflammatory, gastroprotective, antioxidant, tissue repair-inducing effects, suggesting a role in novel drug development. This study investigates in vivo mechanism action of SOL treatment in L. amazonensis-infected BALB/c mice. SOL was isolated from the roots of S. chilensis, and L. amazonensis-infected mice were treated daily with SOL (10, 50, 100 mg/kg) by gavage for 30 days. Gastric (NAG, MPO), hepatic (AST, ALT), systemic (body weight, NO) toxicity, leishmanicidal activity (lesion size, parasite burden), cell profile (macrophage, neutrophil infiltration), antioxidant (ABTS, NBT, NO), oxidant parameters (FRAP, ABTS), Th1, Th2, Th17 cytokines (CBA), collagen deposition (picrosirius), arginase, iNOS, NF-kB, and NRF2 (immunofluorescence) were evaluated. In vivo results showed SOL-treatment did not induce gastric, hepatic, or systemic toxicity in L. amazonensis-infected mice. SOL was able to reduce the lesion size and parasite load at the site of infection, increasing macrophage infiltration and neutrophil migration, exerting a balance in antioxidant (increased ABTS, NBT reduction, and NO), oxidative (increased FRAP and ABTS), and anti-inflammatory responses (reduced TNF-α, IFN-γ and increased IL-6, IL-17 production), and inducing arginase, iNOS, NF-kB, NRF2 and collagen deposition (type III), favoring wound healing and accelerating tissue repair at the site injury.

Inhibition of peroxidases and oxidoreductases is crucial for avoiding false-positive reactions in the localization of reactive oxygen species in intact barley root tips.

NBT and HE may be efficiently used for the detection of superoxide, while DCDHF-DA and DHR123 for the detection of peroxynitrite in intact barley root tips, only ifPRXs and oxidoreductases are inhibited to avoid false-positive reactions. Strong peroxidase (PRX) and oxidoreductase activities were observed in the barley root tips that were markedly inhibited by NaN3. Rapid and strong nitro-blue tetrazolium chloride (NBT) reduction is associated mainly with the vital functions of root cells but not with superoxide formation. In turn, the inhibition of root surface redox activity by NaN3 strongly reduced the formation of formazan, but its slight accumulation, observed in the root elongation zone, was a result of NADPH oxidase-mediated apoplastic superoxide formation. A longer staining time period with NBT was required for the detection of antimycin A-mediated superoxide formation inside the cells. This antimycin A-induced superoxide was clearly detectable by hydroethidine (HE) after the inhibition of PRXs by NaN3, and it was restricted into the root transition zone. TEMPOL, a superoxide scavenger, strongly inhibited both NBT reduction and HE oxidation in the presence of NaN3. Similarly, the DCDHF-DA and DHR123 oxidation was markedly reduced after the inhibition of apoplastic PRXs by NaN3 and was detectable mainly in the root transition zone. This fluorescence signal was not influenced by the application of pyruvate but was strongly reduced by urea, a peroxynitrite scavenger. The presented results suggest that if the root PRXs and oxidoreductases are inhibited, both NBT and HE detect mainly superoxide, whereas both DCDHF-DA and DHR123 may be efficiently used for the detection of peroxynitrite in intact barley root tips. The inhibition of PRXs and oxidoreductases is crucial for avoiding false-positive reactions in the localization of reactive oxygen species in the intact barley root tip.

Antioxidant capacity of wild-growing orange mullein (Verbascum phlomoides L.)

Orange mullein is a biennial plant belonging to the figwort (Scrophulariaceae) family. The vivid yellow flowers are arranged in spikes located on the top of the stem. It is a drought and cold-tolerant plant requiring much sunlight that grows on pastures, roadsides, and in dry weed associations. The aim of this study was to assess the effect of different solvents (water, 70% acetone, 70% methanol, and 70% ethanol) on the assessment of antioxidant capacity of leaves and flowers of orange mullein. Total phenolics are higher in the leaves and reach a value of up to 15.70 mg of gallic acid per one g of dry leaf weight, while flavonoids are more dominant in flowers and reach a value of 5.82 mg of quercetin per one g of dry flower. Correlation was performed between total phenolics, total tannins, total flavonoids, and antioxidant tests. It is the flavonoids that are mainly responsible a the high antioxidant activity establishing a correlation with all the tests performed, including FRAP, ABTS, DPPH, total antioxidant activity, total reduction capacity, and NBT reduction test.

Microphages Count and Activity, a Comparison Study between Radiotherapy Technicians and other Hospital Occupational

Radiotherapy technicians are classified as radiation occupational with continuous exposure to radiation,radiation can damage human cells including Hematopoietic cells. The present study dealt with estimationof both count and activity of peripheral microphages. A total of (23) hospital occupational were tested usingperipheral Microphages count in blood film and phagocytic activity by NBT reduction test. Results showedthat Test group G1 (12 technicians) recorded normal ratios of microphages count; but diminished in theiractivity when compared with control group G2 (11 occupational). Conclusions: there is a great associationbetween radiation exposure dose and Microphage activity even though their counts are within normal range.And that harmful effect can increase due to synergistic effect of poor special PPE supply

Proinflammatory effects of environmental cadmium boost resistance to opportunistic pathogen Aspergillus fumigatus: Implications for sustained low-level pulmonary inflammation?

Cadmium (Cd) is one of the most toxic environmental heavy metals to which the general population is exposed mainly via the oral route. Owing to its immunomodulatory potential, orally acquired Cd affects antimicrobial immune defense in several organs, including the lungs. While there are data concerning Cd and viral and bacterial pulmonary infections, effects on fungal infections are not studied yet. In the present study, the effect of the Cd (5 mg/L for 30 days, in drinking water, the average daily Cd intake 0.641 ± 0.089 mg/kg) on the immune response of rats to pulmonary A. fumigatus infection was examined. Data obtained showed that orally acquired cadmium does not affect the elimination of the fungus in immunocompetent rats owing to the preservation of some aspects of innate immune responses (lung leukocyte infiltration and NBT reduction) and an increase in other (increased numbers of mucus-producing goblet cells, MPO release). Cd does not affect an IFN-γ response in lung leukocytes during the infection (despite suppression of cytokine production in cells of lung-draining lymph nodes), while it stimulates IL-17 and suppresses IL-10 response to the fungus. As a result, the elimination of the fungus occurs in a milieu with the prevailing proinflammatory response in Cd-exposed animals that preserved fungal elimination from the lungs, though with more intense injury to the lung tissue. Therefore, the proinflammatory microenvironment in the lungs created by Cd that sustains inflammatory/immune response to the fungus to which humans are exposed for a lifetime, raises a concern of orally acquired Cd as a risk factor for the development of chronic low-grade pulmonary inflammation.

Abstract 236: Therapeutic targeting of the pentose phosphate pathway in colorectal cancer

Abstract Colorectal cancer is the third most common neoplasia and the second cause of cancer-related deaths worldwide. Unlike normal cells, tumor cells reprogram metabolic pathways to meet their bioenergetics, redox, biosynthetic demands and rely mostly on aerobic glycolysis (Warburg effect). Colorectal cancer cells upregulate the pentose phosphate pathway (PPP), and p53 is a crucial regulator. The PPP is a significant route for glucose catabolism and is required for DNA synthesis of rapidly-proliferating cells. Its oxidative phase (oxPPP), catalyzed by the rate-limiting enzyme glucose-6-phosphate dehydrogenase (G6PD), provides the cell with nicotinamide adenine dinucleotide phosphate (NADPH) that is needed for biosynthetic and detoxifying processes. For the past six decades, 5-Fluorouracil (5-FU) has been the treatment of choice in colorectal cancer. However, 5-FU exhibits high toxicity and drug resistance in patients. Therefore, we hypothesized that targeting the PPP might offer novel therapeutic opportunities in colorectal cancer and improve the response to 5-FU at lower and safer doses. Accordingly, we aim to investigate and characterize the anti-tumor effect of the G6PD inhibitor, 6-aminonicotinamide (6-AN), alone, or in combination with 5-FU on colorectal cancer cells. We explored the effects of oxPPP inhibition on colorectal cancer cell growth, reactive oxygen species (ROS) production, cell cycle regulation, and senescence. We have shown that 6-AN arrested cell growth in HCT116 and HCT116 p53−/− colorectal cancer cells while spared normal-like colon cells (NCM460D). Moreover, 6-AN induced S-phase arrest and early senescence in HCT116 cells as demonstrated by cell cycle analysis using flow cytometry and senescence-associated beta-galactosidase assay, respectively. We also tested the effects of 6-AN/5-FU combination treatments on cellular viability using MTT assay and validated our results using SRB and trypan blue exclusion assays. Interestingly, combination treatments of 6-AN with 5-FU resulted in synergistic effects as estimated using Compusyn software. We used HCT116 colorectal cancer cells resistant to 5-FU (HCT116 5FU-R) or lacking p53, as models for tumor resistance. Importantly, the combination treatment sensitized both HCT116 p53−/− and HCT116 5FU-R colorectal cancer cells to 5-FU and was accompanied by a reduction in G6PD activity and increased ROS using NBT reduction assay. Our findings indicate that combining 6-AN with 5-FU may decrease resistance and further sensitize colorectal cancer cells to 5-FU treatment independently of p53 and drug resistance status. Exploiting this metabolic vulnerability may offer a novel clinical approach and improve patient's therapy. Citation Format: Noorhan Ghanem, Chirine El Baba, Lara Al Saleh, Berthe Hayar, Patrick Aouad, Marwa Al Hassan, Riyad El-Khoury, Julnar Usta, Nadine Darwiche. Therapeutic targeting of the pentose phosphate pathway in colorectal cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 236.

Evaluation of hemato-immunological parameters and stress indicators of common carp (Cyprinus carpio) in different C/N ratio of biofloc system

In spite of various advantages of biofloc technology in aquaculture, few studies have focused on the health status of fish in biofloc system. In this survey, the effect of cane molasses as a carbon source of biofloc system on hemato-immunological parameters, antioxidant status, and stress indicators of common carp (Cyprinus carpio) was investigated. Four hundred and twenty juvenile common carp (40.2 ± 5.76 g) were randomly divided into four equal groups in triplicates as follows: groups A, B, and C were reared in biofloc system with molasses as a carbon source with C/N ratio of 15, 20, and 25, respectively, whereas control group (D) was reared in similar intensity without biofloc system. Fish were reared for 90 days and samples were taken on days 0, 30, 60, and 90 of the experiment. Immunological parameters including serum lysozyme and bactericidal activity, serum complement and IgM level, and NBT reduction and resistance to bacterial challenge as well as hematological parameters (RBC, WBC, hematocrit, hemoglobin) were assessed in experimental groups. Meanwhile, antioxidative enzyme activity (glutathione and superoxide dismutase, catalase) and stress indicators (glucose and cortisol level) were measured and compared among the groups. Water quality parameters were evaluated in all groups. Results showed that most of the immunological parameters as well as resistance against bacterial infection increased in biofloc groups (particularly in C/N = 20 groups) (P < 0.05). Hematological parameters and antioxidative enzyme activity were not affected by biofloc systems. Stress indicators showed a significant decrease in biofloc system, particularly in C/N = 20 group compared with control (P < 0.05). The results indicated that biofloc system (particularly C/N ratio = 20 groups) could not only improve immunological parameters, antioxidative status, and water quality but it decreased stress statues of common carp.

Activities of Succinate Dehydrogenase and Lactate Dehydrogenase in Blood Lymphocytes in Yakut Ground Squirrels Spermophilus undulatus During Hibernation and in the Active State.

We studied energy metabolism in blood lymphocytes of Yakut ground squirrels Spermophilus undulatus in active state and during hibernation. Activities of succinate dehydrogenase (SDH) and lactate dehydrogenase (LDH), marker enzymes of mitochondrial respiration and glycolysis, were measured by a cytobiochemical method based on quantitative assessment of a product of NBT reduction to diformazan in blood lymphocytes immobilized on glass. To measure SDH and LDH activities, cytobiochemical staining of immobilized cells was performed with succinate, lactate, and NAD. In the state of hibernation, SDH activity decreased by 3 times and LDH activity decreased by 10 times or more. These results suggest that the decrease in metabolic activity in lymphocytes of ground squirrels during hypothermia is associated with inhibition of glycolysis, rather than with mitochondrial energy supply.

Growth inhibition and differential induction of human leukemic U937 cells by Chinese medicinal herbs

Effects of boiling-water extracts and 80% (v/v) ethanol extracts from Chinese medicinal herbs on the antiproliferation and differentiation of human leukemic U937 cells were examined. Conditioned medium from peripheral blood monocytes (MNC-CM) stimulated with various levels (200-800 μg/mL) and types of herb extracts (MNC-CM mode) were used to screen the effective herbs. Results showed that among the herbs tested, MNC-CM from boiling-water extracts of Huang Gi (HG), Gan Cao (GC), Lian Zi (LZ), Da Zao (DZ), and Tang Shen (TS) showed remarkable (> 40%) growth inhibition on the U937 cells at high dosage, whereas mixtures of boiling-water extracts of tested herbs with culturing medium displayed insignificant results. Meanwhile, inferior inhibition on cell proliferation was observed when U937 cells were treated with ethanol extracts with MNC-CM or conventional mode. Assays for cytoplasmic superoxide production (NBT reducing ability) by U937 cells induced by ethanol precipitates of boiling-water extracts (100-400 μg/mL) from LZ indicated a dose-dependent positive percentage (31-49%), revealing the apparent differentiation-inducing effect of MNC-CM on U937 cells.

Novel Coupled Molecules from Active Structural Motifs of Synthetic and Natural Origin as Immunosuppressants.

Nitric oxide (NO) is an important mediator in the pathogenesis and control of immune system-related disorders and its levels are modulated by inducible NO synthase (iNOS). Oxidative stress is another pathological indication in majority of autoimmune disorders. The present study aims at the development of coupled molecules via selection of pharmacophores for both immunomodulatory and antioxidant activities through iNOS inhibition. Variedly substituted coumarin moieties are coupled with naturally occurring phenols through an amide linkage and were predicted for activities using computer-based program PASS. The compounds predicted to have dual activities were synthesized. Docking studies were carried out against iNOS (PDB 1R35) and compounds having good docking score were evaluated for immunomodulatory and antioxidant activities. The synthesized compounds were found to be pure and were obtained in good yields. Compounds with maximum docking score (YR1a, YR2e, YR2c and YR4e) were selected for evaluation by in vitro models. Compounds YR2e and YR2c markedly inhibited the reduction of NBT dye and showed maximum % iNOS inhibition. In DPPH assay, compound YR4e was observed as the most potent antioxidant (EC50 0.33 µM/mL). Based on these studies, compounds YR2e and YR2c were selected for haemagglutination test. Compound YR2e was observed as the most active immunosuppressant with maximal inhibitory ability of iNOS and NBT reduction and lower HAT value of 3.5. Compound YR2e can be utilized as a pharmacological agent in the prevention or treatment of immunomodulatory diseases such as tumors, rheumatoid arthritis, ulcerative colitis, organ transplant and other autoimmune disorders.

SRC family kinase inihibitors enhance all-trans-retinoic acid or arsenic trioxide induced differentiation of NB4 Leukemia Cells

Background & Aim Background: The Src family kinases (SFK) are non-receptor tyrosine kinases that have been implicated in a variety of process, including proliferation, survival, differentiation and migration. Recent studies showed that inhibition of SFKs resulted in enhancement of retinoic acid-induced myeloid differentiation. In this study, we investigated whether SFK inhibitor PP2 and FDA approved dual Src/ABL inhibitor (bosutinib or dasatinib) could enhance the differentiation of NB4 leukemia cells when combined with all-trans-retinoic acid (ATRA) or arsenic trioxide (ATO). Methods, Results & Conclusion Methods: We demonstrated the SFK inhibitor PP2 enhanced the differentiation of NB4 cells when combined with ATRA or ATO. Subsequently, we investigated whether bosutinib and dasatinib could enhance the differentiation of NB4 cells when combined with ATRA or ATO. The cells were analyzed for myeloid differentiation marker CD11b expression using flow cytometry. These results were confirmed in morphologic analysis by Wright stain and NBT reduction assay. In addition, we attempted to determine the difference in retinoic acid-induced gene expression. Results Our data showed that SFK inhibitor PP2 enhanced myeloid differentiation when combined with ATRA or ATO. The synergistic effect was significantly stronger when PP2 was combined with ATRA and ATO (triple treatment) than when PP2 was combined with ATRA or ATO (dual treatment). The similar results were obtained when bosutinib and dasatinib were applied instead of PP2. Co-treatment with bosutinib plus ATRA or ATO, and dasatinib plus ATRA or ATO resulted in significant enhancement of CD11b-positive cells when compared to the each treatment group in bosutinib, dasatinib, ATRA, or ATO. Also, the synergistic effects of bosutinib and dasatinib in combination with ATRA were greater than in combination with ATO. Conclusions SFK inhibitor PP2 and dual Src/ABL inhibitor (bosutinib or dasatinib) can enhances the differentiation of NB4 leukemia cells when combined ATRA and/or ATO. These findings suggest that ATRA or ATO combinated with dual Src/ABL inhibitors may have therapeutic beneficial for the treatment of APL patients.

Immunomodulatory Effect of Eriocitrin in Experimental Animals with Benzo(a)Pyrene-induced Lung Carcinogenesis.

Lung carcinogenesis is one of the main sources of cancer-related mortality globally and it is estimated that nearly 1 million people die from it every year. The 5-year survival rate of lung carcinogenesis is reported at just 15%. The aim of the current research was to investigate the immunomodulatory effect of eriocitrin against benzo(a)pyrene [B(a) P]-induced lung tumorigenesis in Swiss albino mice. The lung sarcoma was provoked through oral gavage of B(a)P (50 mg/kg body weight) two times/week for four weeks. CEA, lung weight, lipid peroxidation (LPO), body weight, immuno-globulin (IgG, IgA, and IgM), tumor incidence, serum marker enzymes (LDH, AHH, λ-GT, and 5'-NTs), hematological counts (leucocytes, lymphocytes, neutrophils, absolute numbers of lymphocytes and neutrophils), antioxidants (SOD and CAT), inflammatory modulators (IL-1β, IL-6, and TNF-α), immune complexes (avidity index, phagocyte index, NBT reduction, and SIC) and histopathological changes were analyzed. Moreover, the status of apoptosis proteins (Bax, caspase-9, and caspase-3) and cell proliferative protein (cyclin D1 and cyclin A) expression was determined by Western blot and PCNA by immunohistochemical analysis. B(a)P-challenged cancer-bearing mice exhibited augmented levels of lipid peroxidation, tumor incidence, lung weight, CEA, serum marker enzymes, IgA, SIC, cell proliferative markers, and inflammatory cytokines with concurrent decrease in body weight, antioxidant levels, hematological counts, immunoglobulins, immune complexes, and apoptotic protein expression. The eriocitrin treatments caused significant reversion of all these marker to previous levels. Overall, the results propose the immunomodulatory prospective of eriocitrin against B(a) P-induced lung carcinogenesis on Swiss albino mice.

NLS-RARα contributes to differentiation block and increased leukemogenic potential in vivo

The fusion oncogene, promyelocytic leukemia (PML)-retinoic acid receptor-α (RARα), is crucial for acute promyelocytic leukemia (APL) pathogenesis. Previous studies have reported that PML-RARα is cleaved by neutrophil elastase (NE), an early myeloid-specific serine protease, leading to translocation of the nuclear localization signal (NLS) of the PML protein to the N-terminal of RARα. This study was designed to evaluate the value of NLS-RARα in the early diagnosis of APL. To investigate the potential functional role of NLS-RARα in leukemogenesis, HL-60 and U937 cell lines were transfected with NLS-RARα lentivirus and negative control (LVNC). The results showed that the induced expression of NLS-RARα down-regulated expressions of CD11b, CD11c, and CD14 compared to the LVNC group induced by 1α, 25-dihydroxyvitamin D3(1,25(OH)2D3). This suggested that NLS-RARα overexpression inhibited granulocytic and monocytic differentiation of myeloid leukemia cells. In addition, Wright-Giemsa staining, flow cytometry, respiratory burst assay, and NBT reduction assay all confirmed the importance of NLS-RARα in differentiation. The mechanistic investigations revealed that induced NLS-RARα expression inhibited 1,25(OH)2D3-induced granulocytic differentiation by regulating the cell cycle regulators p19INK4D, p21WAF1/CIP1, cyclinD1, cyclin E1, and pRB. Furthermore, the cleaved protein NLS-RARα enhanced the oncogenicity of U937 cells in NOD/SCID mice. These findings collectively demonstrated that NLS-RARα blocked granulocytic and monocytic differentiation of myeloid leukemia cells by inhibiting the downstream targets of the RARα signal pathway and the cell cycle. This may provide a promising new target and method for diagnosing and treating APL.

Autoimmune process markers in insulin-dependent diabetes mellitus

Quantitative and functional parameters of the monocyte and В-cell immunity were assessed in patients with insulin-dependent diabetes over the course of disease. Studies of the monocyte component in subjects predisposed to disease and of the humoral one in those with clinical manifestations are valuable for predicting the autoimmune process. Signs predicting a poor outcome are increase of the count of Fc-positive cells, decrease of NBT reduction of monocytes in subjects without signs of the disease, high levels of immunoglobulin G in manifest disease, and increase of IgM and B-lymphopcyte count and decrease of IgA over the course of the disease.